<html>
<head>
</head>
<body>
    <h1>设置 HTML</h1>

    <div id="01">
      <h2>Hello China!</h2>
    </div>
    <div id="02">
      <h2>Hello World!</h2>
    </div>
    
    <p id="demo"></p>
    
    <script>
    $(document).ready(function() {
      var myElement = $("#02");
      myElement.html("<h2>Hello Shanghai!</h2>");
    });
    </script>
    
</body>
</html>